The GAs-RhMYB70 feedback loop fine-tunes cell expansion and petal size by modulating cellulose content in rose.

ABSTRACT: Cell expansion in petals plays a crucial role in flower opening and final size in rose (Rosa hybrida), which largely determines its market value. While cell expansion is known to be closely associated with gibberellins (GAs), the underlying molecular mechanism remains elusive. Here, we measured the levels of GAs during flower opening and demonstrated that GA₃ treatment significantly increases petal size. Moreover, we identified RhMYB70, an R2R3 MYB transcription factor, whose expression was inhibited by GA₃ treatment. RhMYB70 silencing resulted in larger petals and petal cell size than those of TRV control. Through transcriptome analysis and biochemical identification, RhMYB70 could directly bind to the promoter of the cellulose synthase gene RhCESA8<

SUBMITTER: Gong F 

PROVIDER: S-EPMC12268152 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature